SMTP Verification Fails in Docker with "Connection refused (os error 111)"

[Nithin6524]

🐛 SMTP Verification Fails in Docker with "Connection refused (os error 111)"

Description

When running the backend server inside a Docker container, SMTP-based email verification fails with the following error:

"message": "Connection refused (os error 111)"

This occurs while attempting to verify email reachability.

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Steps to Reproduce

1. Run the backend service inside a Docker container
2. Trigger email validation for a Gmail address (e.g., nithin6524@gmail.com)
3. Observe the validation response

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Expected Behavior

• SMTP verification should successfully connect to the recipient mail server
• is_reachable should return a definitive value (true or false)

---

Actual Behavior

• SMTP connection fails with:

  Connection refused (os error 111)
  

• is_reachable is returned as "unknown"

---

Relevant Output

"smtp": {
  "error": {
    "type": "IOError",
    "message": "Connection refused (os error 111)"
  }
}

[Nithin6524]

@amaury1093 Can you help me with this issue?

[proxy4smtp]

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